Dietl etal
separation op n-isopropylacrylamide prom
sulpuric acid solutions thereof

ABSTRACT

N-ISOPROPYLACRYLAMIDE IS PRODUCED BY REACTION BETWEEN ACRYLONITRILE AND ISOPROPYL ALCOHOL IN CONCENTRATED SULFURIC ACID. IN ORDER FOR THE N-ISOPROPYLACRYLAMIDE TO BE USED IN VARIOUS INDUSTRIAL PROCESSES IT MUST BE ISOLATED FROM ITS SULFURIC ACID SOLUTION. THIS MAY BE ACCOMPLISHED BY (1) DILUTION OF THE SOLUTION WITH WATER, (2) EXTRACTING THE N-ISOPROPYLACRYLAMIDE CONTENT OF THE DILUTE SOLUTION WITH AN ORGANIC SOLVENT FOR N-ISOPROPLYACRYLAMIDE SUCH AS METHYLENE CHLORIDE OR CHLOROFORM, AND (3) EVAPORATING OFF THE SOLVENT FROM THE N-ISOPROPYLACRYLAMIDE-SOLVENT SOLUTION, WHEREBY PURE N-ISOPROPYLACRYLAMIDE IS OBTAINED.

DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at therequest of the applicant or owner in accordance with the Notice of Dec.16, 1969, 869 0.6. 687. The abstracts of Defensive Publicationapplications are identified by distinctly numbered series and arearranged chronologically. The heading of each abstract indicates thenumber of pages of specification, including claims and sheets ofdrawings contained in the application as originally filed. The files ofthese applications are available to the publlc for inspection andreproduction may be purchased for 30 cents a sheet.

Defensive Publication applications have not been examined as to themerits of alleged invention. The Patent Oflice makes no assertion as tothe novelty of the disclosed subject matter.

PUBLISHED JULY 25, 1972 T900,0]l4 SEPARATION OF N-ISOPROPYLAQRYLAMIDEFROM SULFURIC ACID SOLUTIONS THEREOF Hans K. Dietl, Rte. 8, Seneca Road37664, and Alan E. Lewis, 814 Afton St. 37660, both of Kingsport,

Tenn.

Filed Sept. 25, 1970, Ser. No. 75,423 Int. Cl. C07c 103/00 US. Cl.260561 N 1 Sheet Drawing. 11 Pages Specification N-isopropylacrylamideis produced by reaction between acrylonitrile and isopropyl alcohol inconcentrated sulfuric acid. In order for the n-isopropylacrylamide to beused in various industrial processes it must be isolated from itssulfuric acid solution. This may be accomplished by (1) dilution of thesolution with water, (2) extracting the n-isopropylacrylamide content ofthe dilute solution with an organic solvent for n-isopropylacrylamidesuch as methylene chloride or chloroform, and (3) evaporating oil thesolvent from the n-isopropylacrylamide-solvent solution, whereby puren-isopropylacrylamide is obtained.

Jhnfly 2 1972 H. K. DIETL ETAL mwmm SEPARATION OF N-ISOPROPYLACRYLAMIDEFROM SULFURIC ACID SOLUTIONS THEREOF Filed Sept. 25, 1970 ano mEobc3a9i02 I 2 2 658mm 22 m 9 E x w 23 25:6 53L 2 6w b m E 5 m m E boEoEo 1 2 A E. LEWIS HANSK-DIETL I N VETQRS ATTORNEY$

